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    <title>Document</title>
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        draw()
        function draw() {
            let ctx = document.getElementById("myCanvas").getContext("2d");;
            for (let i = 0; i < 6; i++) {
                for (let j = 0; j < 6; j++) {
                    // ?
                    ctx.strokeStyle = `rgba(0,${Math.floor(255 - 42.5 * i)}`
                    ctx.beginPath();
                    ctx.arc(12.5 + j * 25, 12.5 + i * 25, 10, 0, 2 * Math.PI, true);
                    ctx.stroke();
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